The Collaborative International Dictionary of English v.0.48:

Exclaim \Ex*claim"\, v. t. & i. [imp. & p. p. Exclaimed; p.
   pr. & vb. n. Exclaiming.] [L. exclamare, exclamatum; ex +
   clamare to cry out; cf. OF. exclamer. See Clam.]
   To cry out from earnestness or passion; to utter with
   vehemence; to call out or declare loudly; to protest
   vehemently; to vociferate; to shout; as, to exclaim against
   oppression with wonder or astonishment; "The field is won!"
   he exclaimed.
   [1913 Webster]